I sold a pair of Louboutins on eBay last week. I shipped the shoes out (with a tracking number & insurance). The tracking says it was delivered on Friday. The bidder (who only had 1 feedback before mine.. Stupid me!) just messaged me saying they haven't received the item yet. I have more than enough proof that I did send out the item on time and that it was delivered + I used insurance. I contacted the buyer and told them to contact the USPS. What should I do now? I'm thinking about contacting eBay to give them a heads up on the situation.